This juvenile Belted Kingfisher unknowingly called me over while I was probably 100 feet away shooting Great Blue Herons at the Tualatin River National Wildlife Refuge in August 2010.  I recognized the familiar rattle vocalization she made after landing on the perch.  I stopped what I was doing and walked slowly toward the creek where the bird had landed.  The Kingfisher let me get surprisingly close–maybe 30 feet away.  I used my Canon 40D on a monopod at 1/400, f6.3, 400mm, ISO200, 0EV.  Many times, juveniles have not developed the instinct to fly away at the first sign of danger (humans), and that is likely the reason I was able to walk toward the bird a distance of about 70 feet, without it flying away.  Normally, Kingfishers are very skittish around cars and people, at least in my experience.